System for enhanced detection of a target

Abstract

Disclosed herein is a computer-readable medium having stored thereon computer-executable instructions for providing phase-range data associated with a return pulse of a radar device and second phase-range data associated with a successive return pulse of the radar device. The computer-executable instructions are preferably also for comparing the phase-range data and the second phase-range data to obtain a difference, and for differentiating the difference. In some embodiments of the invention, the computer-executable instructions are preferably also for discriminating a target from clutter by using the differentiated difference to identify coordinates satisfying a velocity threshold associated with the clutter. Embodiments of the invention preferably enable phase-coherent operation of a non-coherent radar device by processing backscattered clutter return, and in some aspects, do so using clutter distributed in range as a reference. Related systems, methods, devices, and other embodiments are also disclosed herein.

1. A computer-readable medium having stored thereon computer-executable instructions for performing the following method:
 providing phase-range data associated with a return pulse of a radar device and second phase-range data associated with a successive return pulse of the radar device; 
 comparing the phase-range data and the second phase-range data to obtain a difference; 
 differentiating the difference; and 
 discriminating a target from clutter by using the differentiated difference to identify coordinates satisfying a velocity threshold associated with the clutter. 
 
   
   
     2. The computer-readable medium of  claim 1 , wherein providing phase-range data and second phase-range data comprises providing an array of phase data as a function of range data and a second array of second phase data as a function of second range data. 
   
   
     3. The computer-readable medium of  claim 1 , wherein discriminating comprises discriminating the target from the clutter by using the differentiated difference to identify coordinates associated with a velocity exceeding clutter velocity. 
   
   
     4. The computer-readable medium of  claim 1 , wherein discriminating comprises:
 identifying clutter behavior; and 
 filtering-out coordinates of the differentiated difference associated with the clutter behavior. 
 
   
   
     5. The computer-readable medium of  claim 4 , wherein identifying clutter behavior comprises at least one of identifying an anomalous change of velocity and identifying an anomalous change of amplitude. 
   
   
     6. The computer-readable medium of  claim 1 , wherein providing comprises providing phase-range data associated with a return pulse of one of a plurality of radar devices and second phase-range data associated with a successive return pulse of the one of the plurality of radar devices. 
   
   
     7. The computer-readable medium of  claim 1 , further comprising computer-executable instructions for extracting the phase-range data and second phase-range data from an in-phase signal and a quadrature signal taken from an intermediate frequency signal of a radar device. 
   
   
     8. A computer-readable medium having stored thereon computer-executable instructions for performing the following method:
 providing phase-range data associated with a return pulse of a radar device, second phase-range data associated with a successive return pulse of the radar device, and amplitude-range data associated with at least one of the return pulse and the successive return pulse; 
 comparing the phase-range data and the second phase-range data to obtain a difference; 
 creating a subset of coordinates from the amplitude-range data that satisfy an amplitude threshold associated with the clutter; 
 building an amplitude mask from the subset; 
 applying the amplitude mask to the difference; 
 differentiating the masked difference; and 
 discriminating a target from clutter by identifying coordinates from the differentiated masked difference satisfying a velocity threshold associated with the clutter. 
 
   
   
     9. The computer-readable medium of  claim 8 , wherein discriminating comprises discriminating the target from the clutter by using the differentiated difference to identify coordinates associated with a velocity exceeding clutter velocity. 
   
   
     10. The computer-readable medium of  claim 8 , wherein discriminating comprises:
 identifying clutter behavior; and 
 filtering-out coordinates of the differentiated masked difference associated with the clutter behavior. 
 
   
   
     11. The computer-readable medium of  claim 10 , wherein identifying clutter behavior comprises at least one of identifying an anomalous change of velocity and identifying an anomalous change of amplitude. 
   
   
     12. A system for discrimination of a target from clutter, the system comprising:
 a computer-readable medium having stored thereon computer-executable instructions for performing the following method:
 providing phase-range data associated with a return pulse of a radar device and second phase-range data associated with a successive return pulse of the radar device; 
 comparing the phase-range data and the second phase-range data to obtain a difference; 
 differentiating the difference; and 
 discriminating the target from the clutter by using the differentiated difference to identify coordinates satisfying a velocity threshold associated with the clutter; and 
 
 at least one computing device for executing the computer-executable instructions stored on the computer-readable medium. 
 
   
   
     13. The system of  claim 12 , wherein the at least one computing device comprises at least one processor and an at least temporary memory. 
   
   
     14. The system of  claim 12 , further comprising:
 means for non-invasively acquiring an intermediate frequency signal of the radar device; and 
 means for downconversion of the intermediate frequency signal to an in-phase signal and a quadrature signal associated with the phase-range data and the second phase-range data. 
 
   
   
     15. The system of  claim 14 , wherein the means for downconversion comprises:
 a coherent oscillator for generating a coherent oscillator signal; and 
 a mixer for mixing the intermediate frequency signal and the coherent oscillator signal. 
 
   
   
     16. The system of  claim 14 , wherein the system is substantially free of a coherent radar device. 
   
   
     17. The system of  claim 14 , further comprising the radar device, and wherein the radar device is in electrical communication with the means for downconversion. 
   
   
     18. The system of  claim 17 , wherein the radar device comprises a non-coherent radar device in electrical communication with the means for downconversion. 
   
   
     19. The system of  claim 14 , comprising a display for showing the discriminated target substantially free of clutter. 
   
   
     20. The system of  claim 19 , wherein the system is substantially free of a coherent radar device. 
   
   
     21. The system of  claim 12 , wherein the target comprises at least a portion of a watercraft. 
   
   
     22. The system of  claim 12 , wherein the target comprises a submarine periscope. 
   
   
     23. The system of  claim 12 , wherein the target comprises at least one of a human and a land vehicle. 
   
   
     24. The system of  claim 12 , wherein the clutter comprises sea clutter. 
   
   
     25. The system of  claim 12 , wherein the clutter comprises at least one of terrain clutter, rain clutter, and discrete clutter. 
   
   
     26. A method for discrimination of a target from clutter, comprising:
 providing phase-range data associated with a return pulse of a radar device, second phase-range data associated with a successive return pulse of the radar device, and amplitude-range data associated with at least one of the return pulse and the successive return pulse; 
 comparing the phase-range data and the second phase-range data to obtain a difference; 
 creating a subset of coordinates from the amplitude-range data that satisfy an amplitude threshold associated with the clutter; 
 building an amplitude mask from the subset; 
 applying the amplitude mask to the difference; 
 differentiating the masked difference; and 
 discriminating the target from the clutter by identifying coordinates from the differentiated masked difference satisfying a velocity threshold associated with the clutter. 
 
   
   
     27. The method of  claim 26 , further comprising deriving the phase-range data, the second phase-range data and the amplitude-range data from an in-phase signal and a quadrature signal associated with an intermediate frequency signal of the radar device. 
   
   
     28. The method of  claim 27 , further comprising downconverting the intermediate frequency signal with a coherent oscillator signal to produce the in-phase signal and the quadrature signal. 
   
   
     29. The method of  claim 28 , wherein downconverting comprises downconverting to produce the in-phase signal and the quadrature signal in an analog format, and wherein the method further comprises converting the in-phase signal and the quadrature signal from the an analog format into a digital format. 
   
   
     30. The method of  claim 28 , further comprising non-invasively acquiring the intermediate frequency signal from the radar device. 
   
   
     31. The method of  claim 30 , wherein non-invasively acquiring comprises non-invasively acquiring the intermediate frequency signal from a non-coherent radar device. 
   
   
     32. The method of  claim 26 , further comprising displaying the discriminated target substantially free of clutter. 
   
   
     33. The method of  claim 26 , wherein discriminating comprises discriminating the target from the clutter by using the differentiated masked difference to identify coordinates associated with a velocity exceeding clutter velocity. 
   
   
     34. The method  claim 26 , wherein discriminating comprises:
 identifying clutter behavior; and 
 filtering-out coordinates of the differentiated masked difference associated with the clutter behavior. 
 
   
   
     35. The method of  claim 34 , wherein identifying clutter behavior comprises at least one of identifying an anomalous change of velocity and identifying an anomalous change of amplitude. 
   
   
     36. A method for discrimination of a target from clutter using an intermediate frequency signal of a non-coherent radar device, comprising:
 acquiring the intermediate frequency signal from the non-coherent radar device; 
 manipulating the intermediate frequency signal to provide phase-range data associated with a return pulse of the non-coherent radar device and second phase-range data associated with a successive return pulse of the non-coherent radar device; 
 comparing the phase-range data and the second phase-range data to obtain a difference; 
 differentiating the difference; and 
 identifying at least one disturbance in a slope of the differentiated difference satisfying a velocity threshold. 
 
   
   
     37. A method for discrimination of a target from clutter using an intermediate frequency signal of a non-coherent radar device, comprising:
 acquiring the intermediate frequency signal from the non-coherent radar device; 
 manipulating the intermediate frequency signal to provide phase-range data associated with a return pulse of the non-coherent radar device and second phase-range data associated with a successive return pulse of the non-coherent radar device; 
 comparing the phase-range data and the second phase-range data to obtain a difference; 
 manipulating the intermediate frequency signal to provide amplitude-range data associated with at least one of the return pulse and the successive return pulse; 
 building an amplitude mask from at least a portion of the amplitude-range data; 
 applying the amplitude mask to the difference; 
 differentiating the masked difference; and 
 identifying at least one disturbance in a slope of the differentiated masked difference satisfying a velocity threshold. 
 
   
   
     38. The method of  claim 37 , further comprising displaying coordinates of the at least one disturbance in the slope that satisfy the velocity threshold. 
   
   
     39. The method of  claim 37 , further comprising creating a subset of coordinates from the amplitude-range data that satisfy an amplitude threshold, and wherein building comprises building the amplitude mask from the subset. 
   
   
     40. A method for substantial removal of relative phase variations from a non-coherent radar device to discriminate a target from clutter, comprising:
 non-invasively acquiring an intermediate frequency signal from the radar device; 
 downconverting the intermediate frequency signal with a coherent oscillator signal to produce an in-phase signal having an analog format and quadrature signal having an analog format; 
 converting the analog format of the in-phase signal and quadrature signal into a digital format; 
 using the in-phase signal and quadrature signal to provide phase-range data associated with a return pulse of the radar device, second phase-range data associated with a successive return pulse of the radar device, and amplitude-range data associated with at least one of the return pulse and the successive return pulse; 
 comparing the phase-range data and the second phase-range data to obtain a difference; 
 creating a subset of coordinates from the amplitude-range data that satisfy an amplitude threshold associated with the clutter; 
 building an amplitude mask from the subset; 
 applying the amplitude mask to the difference; 
 differentiating the masked difference; and 
 discriminating the target from the clutter by identifying coordinates from the differentiated masked difference satisfying a velocity threshold associated with the clutter. 
 
   
   
     41. A method of non-invasively cohering a non-coherent radar device, comprising:
 acquiring an intermediate frequency signal from the non-coherent radar device; 
 manipulating the intermediate frequency signal to provide phase-range data associated with a return pulse of the non-coherent radar device and second phase-range data associated with a successive return pulse of the non-coherent radar device; 
 manipulating the intermediate frequency signal to provide amplitude-range data associated with at least one of the return pulse and the successive return pulse; 
 comparing the phase-range data and the second phase-range data to obtain a difference: 
 building an amplitude mask from at least a portion of the amplitude-range data; 
 applying the amplitude mask to the difference to obtain a masked difference; and 
 differentiating the masked difference. 
 
   
   
     42. The method of  claim 41 , further comprising creating a subset of coordinates from the amplitude-range data that satisfy an amplitude threshold, and wherein building comprises building the amplitude mask from the subset. 
   
   
     43. A method of non-invasively cohering a non-coherent radar device, comprising:
 acquiring an intermediate frequency signal from the non-coherent radar device; 
 manipulating the intermediate frequency signal to provide phase-range data associated with a return pulse of the non-coherent radar device and second phase-range data associated with a successive return pulse of the non-coherent radar device; 
 comparing the phase-range data and the second phase-range data to obtain a difference; and 
 differentiating the difference. 
 
   
   
     44. An enhanced detection system, comprising:
 a coherent oscillator for generating a coherent oscillator signal; 
 a mixer for mixing the coherent oscillator signal and an intermediate frequency signal of a non-coherent radar device to downconvert the intermediate frequency signal to an in-phase signal and a quadrature signal in an analog format; 
 an analog-to-digital converter for converting the analog format of the in-phase signal and quadrature signal into a digital format; 
 a digital signal processor for receiving the in-phase signal and quadrature signal in the digital format and providing phase-range data of a return pulse of the non-coherent radar device and second phase-range data of a successive return pulse of the non-coherent radar device; 
 a computing device for comparing the phase-range data and the second phase-range data to obtain a difference, differentiating the difference, and discriminating a target from clutter by using the differentiated difference to identify coordinates satisfying a velocity threshold associated with the clutter; and 
 a display for showing the discriminated target substantially free of clutter. 
 
   
   
     45. The system of  claim 44 , further comprising the non-coherent radar device.